The present invention pertains to operable wall panels movable to partition large rooms into smaller rooms, and, in particular, to an inverted trolley assembly that eliminates binding of the wall panels when they are moved from a wall-forming position to a stacked position.
Operable walls or partitions, also known as movable wall panel systems, find useful application in a variety of venues, such as classrooms, offices, convention centers and hospitals. In these venues, the operable walls can be utilized to efficiently divide or compartmentalize an interior space into a multitude of separate, smaller rooms. Operable wall panels are typically connected to trolleys that roll within an overhead track. Travel of the trolleys within the track allows the panels to be moved between a stacked arrangement in a storage location, and a wall-forming, extended arrangement in alignment with the overhead track.
One type of movable wall panel system is a continuously-hinged system in which each operable partition is typically hinged to its adjacent partitions. Continuously-hinged wall panel systems are frequently electrically driven between their stacked and extended positions. When arranged in a proper center stacked position, the operable partitions are folded over one another accordion style with each panel or partition being oriented generally transverse to the overhead track.
One shortcoming of continuously-hinged operable partitions is that during partition movement, and usually before unfolding, stacked partitions have a tendency to move along the overhead track away from the location at which they are arranged when properly stacked. For instance, when continuously-hinged operable partitions are extended to form a wall, the leading partition, which is connected to an electric motor via a chain, is pulled from its transverse position at the end of a stacked set of partitions and begins to straighten out. Straightening of the leading partition is normally assisted by guide rails flanking the overhead track which engage the partitions. As the leading partition is pulled off, the remaining stacked partitions, still in a substantially stacked arrangement transverse to the track, often begin to move out in the wall extending direction. This movement is undesirable as these stacked partitions can jam at the guide rails and hinder further wall extension.
The movement of folded partitions may also be problematic when continuously-hinged operable partitions are stacked. During the stacking process, the trailing partitions which first reach the stacking area are manipulated to break and stack. If these stacked partitions move sideways, they may interfere with the stacking of subsequent partitions and frustrate the stacking process. These problems can be aggravated with non-level tracks as gravity may cause some partitions to drift sideways.
An existing assembly or apparatus directed to the problem of movement of stacked panels includes two cables, with loops at each end, and a high tension spring assembly interconnecting the cables. The assembly spring is installed in a recess within the top edge of one partition, and each of the cables is guided through mounted diverters and connected to an adjacent partition. This assembly has several shortcomings. For instance, the assembly is difficult to install, and must be carefully checked and tightened before installation. The separate custom designed components of the assembly are also relatively expensive. Furthermore, the design of the assembly requires that the cables pass within the space normally occupied by the top sweeps, i.e. the space which extends from the room ceiling. The removal of a portion of the top sweeps to accommodate the cables results in a degradation of the acoustical performance of the partition.
Another system developed to address this problem is disclosed in U.S. Pat. No. 5,499,671 which is assigned to the assignee of the present invention. This patent discloses an apparatus that includes first and second camming assemblies which are positioned along the track and cooperate with plates extending from the trolley to resist passage of a panel if the panel is transversely positioned relative to the track. The apparatus includes numerous components including pivots, bearings, rollers, and biasing springs, etc. and also requires adjustment of the components.
Neither of these approaches addresses the problem of binding of the panels during stacking and extending operations with panels suspended from rigidly centered trolleys. Binding can occur during stacking or unfolding where the panels lock up because adjacent panels, both with trolleys, do not have sufficient play at their leading or trailing edge to extend while pivoting on the trolley. This can be dealt with by removing a trolley from adjacent panel pairs; however, this results in the panel being supported solely by the hinge connections to its adjacent panels which adds unnecessary load to the hinge.
Thus, a need remains for an assembly that diminishes the tendency of stacked panels to resist unfolding by moving while remaining in a stacked arrangement and also prevents binding of the panels without the disadvantages of the aforementioned solutions.
The present invention provides an inverted trolley assembly for supporting a movable wall panel from within the panel and interconnecting the movable wall panel to a movable wall system. The inverted trolley includes a carrier having first and second ends with a roller assembly attached to each end. The rollers are positioned to engage the underside of the top frame of the movable wall panel when the inverted trolley is installed within the panel. In a preferred embodiment, spacers are included with the roller assembly to center each roller on its axle. The inverted trolley also includes a trolley block attached to the carrier that is connectable to the external trolley of the track and trolley system.
In another aspect of the invention, there is provided a movable wall panel with a movable trolley attachment in the form of an inverted trolley for connecting the movable wall panel to an external trolley. The wall panel has a top frame at its upper end. The top frame defines a channel and has a top portion that includes an opening in communication with the channel. In a preferred embodiment, the opening is an elongated slot. The inverted trolley assembly is disposed within the channel in the top frame and is movable within the channel. The trolley attachment assembly is accessible through the elongated slot in the wall panel top frame. In a preferred embodiment, the panel also includes a trolley retainer attached to the base of the channel in the wall panel top frame. The trolley retainer has upstanding portions that limit the range of movement of the trolley attachment assembly.
In yet another aspect of the invention, a movable wall system is provided including a track, a plurality of wall panels, each panel having a trolley attachment assembly in the form of an inverted trolley that is movable within a channel in the wall panel top frame, and a second trolley connecting the wall panel and inverted trolley combination to the track for movement of the wall panel along the track.
The invention provides a trolley system that eliminates binding of operable wall panels when folded on a single track centerline.
The invention further provides a trolley system that allows continuously hinged wall panels to have support trolleys on adjacent panels while operating without binding.